His secret life unravelled when investigators discovered he owned three luxury properties in Spain, and had a portfolio of seven others in Wales, six in Cardiff alone.

Recorder Paul Hopkins described him as “professional, well organised and ruthlessly dishonest” as he sentenced him.

Ahmed was jailed after admitting 15 charges, including four counts of money laundering, three counts of mortgage fraud and eight counts of benefit and council tax fraud.

Investigators with Cardiff Council were first to look into his affairs in October 2011.

As inquiries continued the police, the Department of Work and Pension (DWP), the National Crime Agency (NCA) and the Regional Fraud Team and the Regional Asset Recovery Team (WALES) (RART) all got involved.

Forensic investigation of his finances then found he was actively profiting as a property landlord, and had pocketed substantial rental income from his portfolio.

Initial interviews under caution were conducted by DWP and Cardiff Council investigators in early 2012.

Interest from the other agencies was triggered as new evidence emerged.

Ahmed and two other suspects were arrested in May 2013 as part of the multi-agency operation.

He was found to have a considerable property empire running to three luxurious apartments in Murcia, Spain, and was making regular high financial transfers to banks in the country.

The financial investigation also uncovered the sale and purchase of properties, many within the Cardiff Bay area, sourced by false mortgage applications.

Chief inspector Gary Phillips of RART said: “This has been a complex multi-agency investigation into a sophisticated criminal operation which allowed Dean Ahmed to amass a considerable amount of wealth by illegal means. When presented with the weight of evidence he had no option but to plead guilty and we welcome today’s sentence.

“Our focus now shifts to taking away the wealth and assets he has amassed under Proceeds of Crime legislation. This case has shown how well agencies are working together to identify and take action against those who commit this type of crime.

“The case should also serve as a warning to other who may be involved or tempted to commit these kinds of offences. Working together we will find you, and as well as putting you before the courts we will also look to regain every penny which has been obtained by illegal means.”

Russell Harvey, of the DWP Fraud Service, said: “A small number of criminals view our welfare system as free money there for the taking and we are determined to catch them. These benefit thieves cost hardworking taxpayers over £1bn a year and steal funds that should help the most vulnerable.”

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